Geologic and infrastructure factors for delineating areas for clean coal: examples in Texas, USA

Abstract

Texas has a wide variety of areas that can be targeted for new clean-coal facilities. These areas are delineated by mapping spatial linkages between coal-and lignite-bearing formations, groundwater and surface-water resources, and CO 2 sinks in brine formations for long-term CO 2 storage or in mature oil fields with potential for enhanced oil recovery (EOR). However, a variety of infrastructure factors make it feasible to also target numerous areas outside coal and lignite basins in Texas. These infrastructure factors include pipelines for delivery of CO 2 to subsurface sinks and delivery of coal-produced hydrogen to refineries, ease of connection to existing transmission lines, distribution of nonattainment areas where new clean-coal facilities could be constructed and be compliant with strict air-quality standards, and railroads that can transport coal and other feedstock to new cleancoal facilities. Primary regions in Texas where favorably co-located CO 2 source-sink factors related to coal and lignite trends include the Gulf Coast, the Eastern Shelf of the Permian Basin, and the Fort Worth Basin. However, areas outside coal and lignite basins, particularly the Permian Basin where a new clean-coal facility is being planned, also have clean-coal potential because of existing CO 2 pipelines and proximity to EOR fields that can economically sustain new clean-coal facilities.

Study on destabilization failure characteristics and energy evolution law of drilling holes

“…Under the background of carbon peak carbon neutrality, the green and clean utilization of fossil energy such as coal has become the primary task of sustainable development in China, 1,2 and with the continuous demand of coal mine resources, the depth of mine engineering construction is increasing, and the coal and gas protrusion disaster is becoming more and more serious, strengthening the green and clean extraction and utilization of coal mine gas is an important task for the high‐quality development of coal industry 3–7 . Drilling prepumping gas technology can effectively reduce the occurrence of coal mine gas protrusion disaster, and is an important means of coal mine gas management 8,9 . The maturity of large‐diameter borehole technology makes increasing the diameter of borehole one of the most direct and effective methods to improve gas extraction efficiency, but the increase of borehole diameter will be accompanied by the decrease of borehole stability, which leads to a large number of fissures around the borehole to provide flow channels for gas, thus reducing the efficiency of gas extraction 10,11 .…”

“…[3][4][5][6][7] Drilling prepumping gas technology can effectively reduce the occurrence of coal mine gas protrusion disaster, and is an important means of coal mine gas management. 8,9 The maturity of large-diameter borehole technology makes increasing the diameter of borehole one of the most direct and effective methods to improve gas extraction efficiency, but the increase of borehole diameter will be accompanied by the decrease of borehole stability, which leads to a large number of fissures around the borehole to provide flow channels for gas, thus reducing the efficiency of gas extraction. 10,11 Therefore, the destabilization of boreholes is one of the important factors affecting gas extraction efficiency.…”